Old-line diabetes test used for diagnosis

BALTIMORE, Aug. 1 (UPI) -- A blood test used to monitor people under care for diabetes may have far wider use in identifying millions with undetected diabetes, U.S. researchers said.

Dr. Christopher Saudek of the Johns Hopkins University School of Medicine in Baltimore said that the hemoglobin A1c test -- HbA1c -- based on a blood sample, is widely used to keep tabs on how well confirmed diabetics keep their blood sugar, or glucose, in check by showing how much glucose red blood cells have been exposed to for the past 120 days, the average lifespan of the cells.

"The test is a measure of long-term glucose control but doctors don't typically use it to screen for or diagnose the disease," Saudek said in a statement. "There's reason to believe it could help identify many of the estimated 6 million people in the United States who have diabetes but don't know it."

The current screening and diagnostic tests measure only the amount of sugar present at the moment that blood sample is taken. Consequently, Saudek said, these tests are accurate only if patients fast for at least 10 hours before the test because glucose concentrations can vary greatly depending on a person's recent meals.